Function operator+=

include/behaviortree_cpp/contrib/json.hpp:22415–22419

@brief add an object to an array @sa https://json.nlohmann.me/api/basic_json/operator+=/

    /// @brief add an object to an array
    /// @sa https://json.nlohmann.me/api/basic_json/operator+=/
    reference operator+=(basic_json&& val)
    {
        push_back(std::move(val));
        return *this;
    }

    /// @brief add an object to an array
    /// @sa https://json.nlohmann.me/api/basic_json/push_back/